Which structure is primarily responsible for conducting impulses from the AV node to the ventricles?

The Bundle of His is primarily responsible for conducting electrical impulses from the atrioventricular (AV) node to the ventricles. This structure is a specialized bundle of conducting tissue that extends from the AV node into the interventricular septum, where it branches into the right and left bundle branches. These branches further divide into the Purkinje fibers, which are responsible for distributing the electrical signals throughout the ventricles, ensuring they contract in a coordinated manner.

The function of the Bundle of His is crucial in the cardiac conduction system, as it serves as the only pathway through which impulses can travel from the atria to the ventricles. This separation of the atrial and ventricular contraction is essential for efficient heart function.

Other options do not fulfill the role of conducting impulses from the AV node to the ventricles. The sinoatrial node is the primary pacemaker of the heart, generating impulses that initiate the heartbeat but do not directly conduct to the ventricles. The myocardium refers to the heart muscle itself and is responsible for the contraction of the heart but is not involved in the transmission of electrical impulses. Purkinje fibers play a role in conducting impulses but do so after the impulses have been transmitted through the Bundle of His.